The development of automated equipment for the analysis of cellular proliferation, enzyme function, apoptosis, cell-cell interactions, and receptor-ligand studies has greatly facilitated research in these areas. The Wallac Microbetaplate Trilux harvester and Victor multilabel counter are components of an integrated system that measures radioactivity, chemiluminescence, fluorescence, and photometry. This equipment allows for analysis of a large number of samples in an automated fashion and can be used for quantitative measurement of labeled molecules. Its versatility should greatly enhance the progress of MH supported research. Due to the major cost involved in its purchase, the instrument must be considered for shared-use. This proposal outlines the Research Plans of six major users and requests funding for its purchase. The NIH funded research outlined encompass a broad range of technologies that will all greatly benefit from use of this equipment. The six major users are all members of the Channing Laboratory and have a strong history of collaboration and scientific interaction. The shared use of this instrument will exemplify the model of the Channing Laboratory in which resources are pooled to strengthen the overall research effort of its members. The use of the proposed instrument should serve to fortify this effort. In summary, this proposal requests funds for the purchase of a Wallac Microbetaplate Trilux harvester and Victor multilabel counter that will be shared by six major users. A major commitment has been made by these users, including the Director of the Channing Laboratory, to provide the financial support required to maintain and operate the instrument. The availability of the instrument will greatly accelerate the MH funded research outlined.